The
ever present Rio de Flag, a runoff stream that originates in the
southwestern slopes of the San Francisco Peaks, continues to be the nexus
of Flagstaff both geographically and culturally. Since settlers from
Boston mounted Old Glory on a ponderosa pine, the Rio de Flag has provided
opportunity for growth and occasion for destruction.

"It's a serious problem," said Joseph Meehan, a director of the Arizona
Historical Society. "It can be a tremendous flood."

In an attempt to curb the flood, the city of Flagstaff is working with
the U.S. Army Corps of Engineers to redirect the fluctuating stream.

The diversion is expected to exceed $20 million. Flooding along the Rio
de Flag during the last 100 years has swallowed roads and ruined property
to a massive extent, although speculation as to the exact amount is purely
that, speculation.

Nevertheless, an even more devastating flood could occur, causing
hundreds of millions of dollars worth of damage, flooding homes,
businesses, the college campus and even city hall.

Even if the "100 year flood" does not happen for several more years -
or ever - the city of Flagstaff suffers from the very presence of the
floodplain in terms of lack of opportunity of development, renovation,
property value and expansion. The subject is broad, and to understand the
Rio de Flag takes both breadth and depth.

Bubbling from Leroux Spring on the San Francisco Peaks, the stream we
know as Rio de Flag gains volume from other tributaries and springs as it
drops into Flagstaff. Depending on snow pack, ground saturation and
precipitation, the Rio de Flag can run almost bone dry or become a raging
torrent.

In places like the narrows, a region bordering North Fort Valley Road,
the current can move at more than 4,500 cubic feet per second, a massive
flood gouging the earth and sweeping away anything in its path.

But this stream is mostly a pleasant resident of the Flagstaff area. It
supplies a duck pond by Flagstaff Middle School and provides tranquility
to Wheeler Park and the public library.

During the late 19th century, settlers built in a 100 year flood plain,
and the watershed surrounding the area was extremely prone to flooding.

The 100 year floodplain title does not necessarily mean an epic flood
occurs every century. Instead, the title is a gauge for both severity and
probability. There is an approximate one in 100 chance of the type of
flooding the early 20th century saw every year which can sometimes happen
several times a year.

The last major flooding in terms of discharge occurred in 1938. Meehan
explains the magnitude of the event.

"The water (on Aspen Avenue) was described by residents as deep enough
to swim a horse. People used to take rowboats to cross it," Meehan said.
"It was an incredible flood and it showed what the Rio could do."

In response to the problematic runoff, many diversions were constructed
through the years. The original flow of the stream bordered Historic Route
66, but business owners along the banks feared damages. Citizens used
every means necessary to redirect the natural course of the runoff,
including dynamite.

In 1983, the Federal Emergency Management Agency announced the area a
flood zone; requiring developers to buy flood insurance or elevate above
the FEMA flood zone depth. Development in the area since has come to a
stand still.

But years of unregulated building combined with previous redirection
had residences backed by a narrow and shallow channel. Many historic
buildings lay entirely in the possible flood's path, threatening records
of a rich history.

Small culverts blocked frequently and in 1993, waters flooded
Continental Country Club, resulting in the biggest volume of floodwater in
Flagstaff history. However, the creation of "Lake Continental" was the
result of a mere 25-year flood. A bigger flood could cause an estimated
$100 million to $500 million worth of damage.